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UUID / GUID Generator

Generate universally unique identifiers (UUIDs/GUIDs). Supports v1, v3, v4, v5, and v7 with bulk generation and formatting options.

Configuration

Generated UUIDs

Click 'Generate' to create UUIDs

About this tool

The UUID / GUID Generator allows you to create Universally Unique Identifiers (UUIDs), also known as Globally Unique Identifiers (GUIDs). These 128-bit values are used widely in software development to uniquely identify information without requiring a central registration authority.

Supported Versions

Version 1 (Time-based)

Generates a UUID based on the current time and the MAC address of the computer generating it. Useful when you need to know the time of creation.

Version 3 (MD5 Name-based)

Generates a deterministic UUID by hashing a specific namespace and name using MD5. The same namespace and name will always produce the same UUID.

Version 4 (Random)

Generates a UUID based completely on random (or pseudo-random) numbers. This is the most common version and provides a very high probability of uniqueness.

Version 5 (SHA-1 Name-based)

Similar to Version 3, but uses SHA-1 hashing. It is deterministic and is generally preferred over Version 3.

Version 7 (Time-ordered)

A newer standard that combines a Unix timestamp with random data. This produces UUIDs that are sortable by creation time, which is highly beneficial for database indexing and performance.

Formatting Options

You can customize the output of the generated UUIDs to match your needs:

  • Quantity: Generate hundreds or thousands of UUIDs at once.
  • Uppercase: Convert the output to uppercase (e.g., 123E4567-E89B-12D3-A456-426614174000).
  • Include Hyphens: Standard UUIDs include hyphens, but you can remove them for a compact 32-character hex string.
  • Wrap in Braces: Enclose the UUID in curly braces {} (common in Microsoft environments).

Namespaces for v3 & v5

For name-based UUIDs, you must provide a name and a namespace. Predefined namespaces according to RFC 4122 are provided:

  • DNS: For fully qualified domain names (e.g., example.com).
  • URL: For URLs (e.g., https://example.com/item).
  • OID: For ISO OIDs.
  • X500: For X.500 DNs.

You can also provide your own custom UUID to act as the namespace.

Credits

This tool is powered by the popular open-source uuid library, which implements RFC 4122 and RFC 9562 compliant algorithms.